GM's redesigned 2014 Chevrolet Silverado crew-cab pickup, due on sale in the second quarter of next year. / GM

by James R. Healey, USA TODAY

by James R. Healey, USA TODAY

PONTIAC, Mich. -- General Motors shows off its most important new vehicles today, the overdue 2014 Chevrolet and GMC full-size pickups.

Delayed by GM's visit to Chapter 11 bankruptcy reorganization in 2009, their re-do now must be strong enough to compensate for the lag. From GM's view, they simply must be that good; the alternative is unthinkable.

"There's nothing more core to our business than our pickup trucks," said Mark Reuss, president of GM's North American operations, at the unveiling of the new trucks here today.

The full-size Chevy Silverado and GMC Sierra are the company's biggest sellers and biggest earners, and they run head-on into Chrysler's updated 2013 Ram and Ford's F-150, updated in 2011, freshened for 2013 and heavily advertised the whole time. Both have challenged GM's aging trucks for sales and market share. The new trucks also will be the platform for GM's new full-size SUVs coming in early 2014, probably as 2015 models.

"This (launch) is incredibly, crazy-important for GM. These trucks will have to hit it out of the park," says Rebecca Lindland, veteran auto industry analyst at consultant IHS Automotive.

Normally, such marquee machines would make their public debut at the North American International Auto Show in Detroit next month. But that'll be the stage for another GM redesign, the seventh-generation Chevrolet Corvette. The concern within GM is that Corvette's star would have outshone the financially vital trucks at the show.

Thus, the introduction for these trucks here at the Michigan Motion Picture Studios, a month ahead of the Detroit show. They'll go on sale, beginning with crew cabs, in the second quarter as 2014 models. Pricing wasn't announced.

What the trucks lack compared with rivals is notable:

-- No eight-speed automatic transmission to match the Ram's. The GM trucks have six-speed gearboxes. Properly executed, a transmission with more speeds, or ratios, can provide better acceleration, better mileage and a more refined driving feel.

-- No obvious equivalent to the F-150's EcoBoost turbocharged V-6 premium engine, which has more power and slightly better fuel economy than the F-150 5-liter V-8.

"Truck buyers won't say, 'I'm not going to buy that truck because it doesn't have an eight-speed automatic'," or some other specific feature -- as long as it performs well overall, says industry watcher Jesse Toprak at TrueCar.com.

Good news for GM: "Those trucks have loyal buyers," he says. "From our perspective, (GM) will have to try hard to mess up."

And despite lack of a marquee feature such as Ford's EcoBoost, the engines in GM's redone trucks jump pretty far forward. The trio of engines -- called EcoTec3 and bestowed with the auto industry's favorite designator, "all-new" -- have fuel-saving direct fuel injection, cylinder deactivation and lightweight aluminum blocks instead of cast iron. The V-6 gets variable valve timing in addition to the other upgrades. The V-8s have had variable valve timing, and that continues.

Such features can be a big deal -- more power, better mileage, fewer emissions. GM says horsepower, torque and fuel-economy ratings will be announced early next year.

While the engines continue the displacements familiar to GM truck fans -- 4.3-liter V-6, 5.3-liter V-8, 6.2-liter V-8 -- they honestly are all-new, insists Jeff Luke, GM's executive chief engineer for full-size and midsize trucks. They share "just a few part numbers" with current engines of the same displacement, he says. The 4.8-liter V-8 is discontinued.

Taking a swipe at Ford's EcoBoost approach for better fuel economy, Luke said at the unveiling today: "Some competitors are resorting to smaller-displacement engines from passenger cars. ... We think cylinder deactivation (running on four cylinders under light load instead of six or eight) is superior."

The most obvious changes for the new GM trucks are more dramatic styling and revamped, upgraded interiors. Outside, squared-off bulges around the wheel wells resemble the look of the successful GMC Terrain two-row SUV. Inside, an 8-inch touch screen in the middle of the dashboard on most models catches up to what designers are doing inside cars and SUVs.

That's what truck buyers want, says Luke. "Don't let the work boots fool you. Truck customers are among the most discerning and demanding in the business."

Less obvious, but arguably more important changes in the new trucks:

-- A chassis redesigned for less noise, more comfort, better handling. Reuss says pickups often are or double as family vehicles and should be refined enough to fill that role gracefully, as well as handle truck tasks.

-- Changes to the cargo bed to be more useful and durable. The bed has tie-down hooks that are beefed-up and rated to restrain 500 pounds each. The trucks also offer optional LED lights under the bed rails. Truckers who use bed covers should find those particularly useful.

-- Bigger rear doors on crew-cab models so rear seat users can enter and exit easier. GM had fallen well behind rivals in rear-seat room and ease of use.

-- A bigger cargo box available on crew-cab models. In addition to the nominal 5 1/2-ft. bed standard across the industry on crew-cab trucks, the new GMs also will offer a 6 1/2-foot bed. While new to GM, it's not unique among full-size pickups.

-- The extended-door cab models get conventional, front-hinged rear doors. They should be more convenient that the rear-hinged back doors on current extended-cab models. Those require the front door to be open before the rear door can be operated.

The list of improvements in the new trucks is long, which could compound GM's task of trimming an overstock of unsold 2012 and 2013 trucks, 183 days worth at the end of November, or more than twice the normal supply. If GM fire-sales those to make way for these upgraded 2014s, it could end up cutting into the pool of potential buyers for the new trucks. Many will opt to buy the current-generation trucks at big discounts rather than gambling that the new ones will be better enough to justify higher prices.

The overstock's threat to the new models "is unfortunate," Lindland says. "It would be catastrophic if these (2014s) don't sell well. You can't overstate how important these trucks are to GM."

GM built up inventory intentionally to ensure it wouldn't run short during production downtime to revamp factories for the 2014s. But it overshot as rivals began heavy discounting, soaking up truck buyers, just as GM was trying to wean itself from huge pickup incentives in order to boost profits.

An analysis by Edmunds.com shows that Chrysler raised Ram incentives 48.9% in the year that ended in November. Ford incentives on the big F-series rose only about 1%. Meanwhile, Edmunds.com says, GM cut its incentive spending on pickups by 4.8%.

Edmunds.com says that even with the new incentives, it still took an average 95 days to sell a Ram, as of November. An F-series took 81 days. GM pickups sat for 101 days before selling.

Now, GM says it'll go back to heavier discounting to help dealers clear the glut of unsold Silverados and Sierras.

Analysts such as Toprak say the simplest solution, but one out of GM's control, would be an improving U.S. economy. "A lot of buyers of full-size trucks are small businesses, and they're not feeling a recovery yet," he says. "There's still some hesitation" about buying new trucks.

But if the housing market continues to creep back, and other signs of recovery are visible, "pent-up demand, and businesses generally feeling better about things, will bring a lot more into the market for $40,000 trucks," Toprak says.

Even if all that works out, GM's new pickups also face a wall of competition around the corner.

-- Ford is expected to launch a fully redone F by 2015 that is likely to make extensive use of aluminum to cut weight and improve mileage.

-- The currently moribund Nissan Titan is due for replacement in 2014 or 2015 and could include a diesel engine previously unavailable, a heavy-duty version, or both.

Some buyers would like the better mileage and longer lifespan of diesels without having to pay the higher prices and without having to put up with the less-refined personalities of heavy-duty pickups.

Making the Silverado and Sierra seem different, even though they're based on the same hardware, has been an ongoing problem. At the unveiling, GM took unusual pains to differentiate.

Journalists had to choose whether to connect to the Internet via the GMC link (password 2014Sierra) or the Chevy link (password Silverado). No functional difference, just trying to make the point.

For briefings on specifics about the two trucks, the Chevy and GMC were far apart, in different settings. Silverado's display featured a bass boat with monster engine, off-road motorcycles and a woodsy mural. The Sierra's setting included a horse trailer, Airstream trailer and a mural of a fancy kitchen with pine flooring.

Even the lunches were different. Chevy fare included hot dogs and macaroni and cheese. GMC had, well, less-recognizable dishes.